Modeling the Differences in Counted Outcomes using Bivariate Copula Models: with Application to Mismeasured Counts

This paper makes three contributions. First, it uses copula functions to obtain a flexible bivariate parametric model for nonnegative integer-valued data (counts). Second, it recovers the distribution of the difference in the two counts from a specifed bivariate count distribution. Third, the methods are applied to counts that are measured with error. Specifically we model the determinants of the difference between the self-reported number of doctor visits (measured with error) and true number of doctor visits (also available in the data used).

Primordial Magnetic Field Limits from Cosmic Microwave Background Bispectrum of Magnetic Passive Scalar Modes

Primordial magnetic fields lead to non-Gaussian signals in the cosmic microwave background (CMB) even at the lowest order, as magnetic stresses and the temperature anisotropy they induce depend quadratically on the magnetic field. In contrast, CMB non-Gaussianity due to inflationary scalar perturbations arises only as a higher order effect. Apart from a compensated scalar mode, stochastic primordial magnetic fields also produce scalar anisotropic stress that remains uncompensated till neutrino decoupling. This gives rise to an adiabatic-like scalar perturbation mode that evolves passively thereafter (called the passive mode). We compute the CMB reduced bispectrum ($b_{l_{_1}l_{_2}l_{_3}}$) induced by this passive mode, sourced via the Sachs-Wolfe effect, on large angular scales. For any configuration of bispectrum, taking a partial sum over mode-coupling terms, we find a typical value of $l_1(l_1+1)l_3(l_3+1) b_{l_{_1}l_{_2}l_{_3}} \sim 6-9 \times 10^{-16}$, for a magnetic field of $B_0 \sim 3$ nG, assuming a nearly scale-invariant magnetic spectrum . We also evaluate, in full, the bispectrum for the squeezed collinear configuration over all angular mode-coupling terms and find $l_1(l_1+1)l_3(l_3+1) b_{l_{_1}l_{_2}l_{_3}} \approx -1.4 \times 10^{-16}$. These values are more than $\sim 10^6$ times larger than the previously calculated magnetic compensated scalar mode CMB bispectrum. Observational limits on the bispectrum from WMAP7 data allow us to set upper limits of $B_0 \sim 2$ nG on the present value of the cosmic magnetic field of primordial origin. This is over 10 times more stringent than earlier limits on $B_0$ based on the compensated mode bispectrum.Comment: 9 page

Assessment of physico- chemical properties and microbial community during composting of municipal solid waste (Viz. KItchen waste) at Jhansi City, U.P. (India)

Rapid industrialization and population explosion in India has led to the migration of people from villages to cities, which generate thousands of tons of Municipal Solid Waste (viz. Kitchen waste) MSW (Viz. KW) daily. Jhansi City is well known district of Bundelkhand region of Uttar Pradesh (India) with a geographical area of 502.75 thousand hectare. The district is situated in the South West corner of the region at 24º11' - 25º57' N latitude and 78º10' - 79º23' E longitudes. Population of Jhansi city is near about 4,79, 612. A detail study was conducted in four consecutive years to assess the potential and possibilities of MSW (Viz. KW) composting generated from Jhansi city, Uttar Pradesh. In the present study, we studied physico-chemical parameters and succession of microbial populations during composting process of MSW (Viz. KW) and found that the pH ranged between 7.1-7.9, Temperature 14-65.2°C, Organic Carbon 20-26 %, moisture content  22-66.7 %, nutrients N – 1.16 %, P – 0.04 %,  K – 0.34%, Na – 2.89 % and microbial colonies like Bacteria, fungi, and Actinomycetes were also present in large numbers.Temperature plays an important role in the growth of microbial colonies during composting of Municipal Solid waste (Viz. Kitchen Waste)

Investigation of complete and incomplete fusion in 7^{7}Li+124^{124}Sn reaction around Coulomb barrier energies

The complete and incomplete fusion cross sections for $^{7}$Li+$^{124}$Sn reaction were measured using online and offline characteristic $\gamma$-ray detection techniques. The complete fusion (CF) cross sections at energies above the Coulomb barrier were found to be suppressed by $\sim$ 26 \% compared to the coupled channel calculations. This suppression observed in complete fusion cross sections is found to be commensurate with the measured total incomplete fusion (ICF) cross sections. There is a distinct feature observed in the ICF cross sections, i.e., $\textit{t}$-capture is found to be dominant than $\alpha$-capture at all the measured energies. A simultaneous explanation of complete, incomplete and total fusion (TF) data was also obtained from the calculations based on Continuum Discretized Coupled Channel method with short range imaginary potentials. The cross section ratios of CF/TF and ICF/TF obtained from the data as well as the calculations showed the dominance of ICF at below barrier energies and CF at above barrier energies.Comment: 9 pages, 8 figure

Electrostatic- and Parallel Magnetic Field- Tuned Two Dimensional Superconductor-Insulator Transitions

The 2D superconductor-insulator transition in disordered ultrathin amorphous bismuth films has been tuned both by electrostatic electron doping using the electric field effect and by the application of parallel magnetic fields. Electrostatic doping was carried out in both zero and nonzero magnetic fields, and magnetic tuning was conducted at multiple strengths of electrostatically induced superconductivity. The transitions were analyzed using finite size scaling with critical exponent products nu*z = 0.65-0.7. The parallel critical magnetic field increased with electron transfer as (dn_c-dn)^0.33, where dn is the electron transfer and dn_c is its critical value, and the critical resistance decreased linearly with dn. However at lower temperatures, in the insulating regime, the resistance became larger than expected from extrapolation of its temperature dependence at higher temperatures, and scaling failed. These observations imply that although the electrostatic- and parallel magnetic field- tuned superconductor-insulator transitions would appear to belong to the same universality class and to be delineated by a robust phase boundary that can be crossed either by tuning electron density or magnetic field, in the case of the field-tuned transition at the lowest temperatures, some different type of physical behavior turns on in the insulating regime.Comment: About 11 pages, with 14 figures. To be submitted to Phys Rev

Non-Supersymmetric Attractors in String Theory

We find examples of non-supersymmetric attractors in Type II string theory compactified on a Calabi Yau three-fold. For a non-supersymmetric attractor the fixed values to which the moduli are drawn at the horizon must minimise an effective potential. For Type IIA at large volume, we consider a configuration carrying D0, D2, D4 and D6 brane charge. When the D6 brane charge is zero, we find for some range of the other charges, that a non-supersymmetric attractor solution exists. When the D6 brane charge is non-zero, we find for some range of charges, a supersymmetry breaking extremum of the effective potential. Closer examination reveals though that it is not a minimum of the effective potential and hence the corresponding black hole solution is not an attractor. Away from large volume, we consider the specific case of the quintic in CP^4. Working in the mirror IIB description we find non-supersymmetric attractors near the Gepner point.Comment: Added a few clarification

Circular Capacitance Micromachined Ultrasonic Transducer

Capacitance micromachined ultrasonic transducers (CMUTs) have become an attractive alternative to the piezoelectric transducers, especially in air-coupled nondestructive evaluation (NDE) and ultrasound medical imaging flow metering,  micro/nanoelectronics, and industrial cleaning, etc. These are similar to other capacitance transducers as these employ a vibrating membrane to send and receive ultrasound in air and water. This paper describes the theory and design of a circular micromachined ultrasonic transducer which could lead to a CMUT with many advantages, including less loading effect. The software programs (Intellisuite 8.2 and MATLAB 7.0) were used to model a single cell of CMUT. The simulations-based studies of the critical parameters like collapse voltage and snapback voltage, which influence the operation of the CMUTs to a large extent, has been discussed. Small signal equivalent circuit model for the circular CMUT has been discussed and the program (SPICE) has been used for the simulation of the small signal equivalent circuit.Defence Science Journal, 2009, 59(6), pp.627-633, DOI:http://dx.doi.org/10.14429/dsj.59.156

Combined local-density and dynamical mean field theory calculations for the compressed lanthanides Ce, Pr, and Nd

This paper reports calculations for compressed Ce (4f^1), Pr (4f^2), and Nd (4f^3) using a combination of the local-density approximation (LDA) and dynamical mean field theory (DMFT), or LDA+DMFT. The 4f moment, spectra, and the total energy among other properties are examined as functions of volume and atomic number for an assumed face-centered cubic (fcc) structure.Comment: 15 pages, 9 figure